Cleaning device for rotary drilling tools



Dec. 9, 1930. Y J. A. z'UBLLN ET Al.

v CLEANING DEVICE FOR ROTARY DRILLING TOOLS Patented Dec. 9, 1930 UNITED STATES PATENT. OFFICE JOHN A. ZUBLIN, OF LOS ANGELES, AND ELMER T. SCOTT, 0F BELL, CALIFORNIA; SAID SCOTT ASSIGNOR TO SAID ZUBLIN CLEANING DEVICE FOR ROTARY DRILLING TOOLS Application led January 5, 1929. "Serial No. 330,526. i

Our invention relates to rotarybits used in drilling wells, and consists of a rotary bit having a rotatable' cutter and a novel means for cleaning the cutter while it is operating in the Well. I

In the well-drillin art, the bit is secured to the lower end o the drill pipe` which rotates it and carries'rotary fluid to it. The rotary Huid issues from the bit and carries the cuttings upward around the drill pipe.

Teeth on different types of bits have different cutting actions, but where the cutters have a more or less-rolling motion relative to the strata, the spaces between the teeth become lled with cuttin s which pack in place and seriously impair ti the bit. This is especially true when drilling in sticky formations.

It is an object of this invention to -provide a device for cleaning the space between the teeth on a bit having a rotatable cutter, this device operating to direct a flow of fluid therebetween.

The direction of this iiow is important, and we have found it desirable to provide a nozzle which is adjustable relative to the shank of the bit so that the jet of fluid passing therethrough may be directed 4tangen-l tially against the cutter, this jet passing between the cutter teeth.

It is a further object of this invention to provide an adjustable nozzle means for directing a jet of fluidtangentially against a cutter and between the teeth thereo A further object of our invention is to provide a bit of this nature in which th I nozzle directs a washing stream onto the body and between those teeth which are momentarily not working.

Further ob'ects and advantages of this invention will e made evident hereinafter.-

In a co-pending application entitled Rotary bit for reciprocating motion, invented b- John A. Zublin, filed September 8, 1925,

rial No. 54,874, there isI disclosed a pare cutting qualities of" ticular type of rotary bit on which the nozzle l'means of our invention has proved particularly satisfactory. We will thus describe our invention as applicable to this type of bit without limiting ourselve's thereto.

Referring particularly to the drawing,- Fig. 1 is a utility view diagrammatically illustrating the drilling apparatus.

Fig. 2 is a view, partially in section, of'J the rotary bit shown in Fig. 1.

Figs. 3 and 4 are sectional viewstaken on their respective lines indicated in Fig. 2.

Referring particularly to Fig. 1, we have illustrated a bore hole 10 being formed by a rotary bit 11 incorporating the features of this invention. The rotary bit 11 is rotated by a drill pipe 12 which extends upward to the surface of the ground and is turned by a rotary machine 13 positioned' above a iioor 14 of a derrick structure. A swivel 15 is connected to the top of the drill pipe and is supported by a travelling block 16 in a manner to control the pressure of the bit 11 on the bottom of the hole. Rotary mud is adapted to be pumped from a sump 17 by a pump 18 anddelivered through a flexible hose' 19 to the swivel 15, whence this fluid passes downward through the drill pipe and through the rotary .nected to the lower end of the drill pipe 12 by a collar 22 which has an opening 23 communicating with the interior of the drill' pipe 12 and through which the fluid passing downward therethrough passes.y i

The shank 21 has an offset portion 26. A pin 27 is formed on the lower end of the ofset portion 26 with its axis lying along the line A-A, this axis being oblique relative to the axis of rotation of the shank 21.

Threaded into an openin 28 of the pin 27 is the head of a thrust mem er 30, this member having a concentric bearing projection 31 extending downward therefro Adapted to fit over the thrust member and the pin 27, and to be rotatable relative thereto is a cutter 33 which comprises a body 34 having an opening 35 therein which is larger` in diameter than the outer diameter of the pin 27 or thrust member 30. A bearing face 36 is formed on the body 34 and extends between the opening 35 andl an opening 37, this latter opening being only slightly larger tha-n the outer diameter of the projection 31 which serves as a radial bearing. The face 36 is adapted to bear against the thrust member 30 when the bit is in operation.

The cutter 33 is held on the pin 27 by means of a series of balls 38 which are positioned in v a race 39 formed in the periphery of the pin 27. These balls are inserted after the cutter 33 is in its position shown in Fig. 2, this insertion taking place through a suitable opening which is subsequently closed byv a lock member 40 clamped in place by a lock screw 41 which passes therethrough and is threaded into the in 27 Exten ing downward from the cutter 33 is a series of lower or drill teeth 45 eachof which is shaped substantially as shown in Fig. 2, and a series of upper or reaming teeth 46 also shown in Fig. 2. Fig. 4 clearly illusltrates these series of teeth, and the offset V:relationship therebetween. It will be noticed that a space 47 exists between each of the teeth 46, while a similar space 48 exists between each of the teeth 45.

During the time that such a bit is being rotated, rotary mud `is supplied to the drill pipe12 and passes downward therethrough and through the opening 23 of the collar 22. This mud subsequently passes through a fluid passage 50 formed through the shank 21 and pin 2 and through a passage 51 formed axially through the thrust member 30. A major portion of the Huid entering the passage 51 passes therefrom between the teeth 45, and acts to move any cuttings upward-to the surface of the ground in the space between' the drill pipe and the bore hole. However, a small portion of this fluid passes through a passage 52 communicating with the passage 51 and with a channel 53 formed, in the surface of the thrust member 30 which contacts the shelf 36. This fluid` rises in the opening 35 and lubricates the balls 38, as well as the engaging surfaces of the cutter and thrust member 30.

The most important feature of the present invention lies in the providin of a suitable nozzle means4 60 which is place in a side passage 61 which communicates 'with the opening 23- of the collar 22. This nozzle means 60 comprises a nozzle body 62 which is threaded into the side passage 61 in the embodiment shown 1n Fig. 2. However, we are not limited to this threaded engagement of the nozzle body 62 relative to the side passage 61.

Formed through the nozzle body 62 is an ori-` tice 63 so positioned that by turnin the nozzle body 62, the direction of flow of e stream of fluid passing through this orifice may be readily changed. We have shown the orice 63 as being eccentrically placed in the nozzle body 62, this. orifice being parallel to the'axis of the nozzle body.

We have found it desirable that the jet of iuid leaving the nozzle means should be directed substantially tangentially along .the exterior of the body 34 of the cutter 33. This jet is thus successively directed throu h the spaces 47 between the teeth 46, all o these spaces being cleaned when the cutter 33 has made one revolution relative to the shank 21. The jet issuing from the orifice 63 also tends to clean the spaces 48 between the lower or drilling teeth 45 although this action is not as pronounced as that cleaniig action which takes lace in the spaces 47. owever, it has been ound that the drilling teeth 45, due to their peculiar swing and scraping cutting motions, are not as susce tible to being balled-up by cuttings w en penetrating sticky formations as are the spaces 47 between the teeth 46, these latter teeth having more of a rolling motion with a lesser de ee of scraping action, and it ison cutters aving such roller motions that ourinvention is most ap licable, inasmuch as these cutters become qulckly clogged when enetrating certain types of formations. Tlie jet issuing from the nozzle is directed between the teeth which are momentarily not working.

A jet of very matrial force is formed by the orifice 63. This is adequately demon.- strated by the polish on the teeth 46 after a bit of this type has been in operation, these teeth being polished by the foreign particles ordinari y carried by the rotary mud which is used as a fluid for carrying the cuttingsV upward.

The teeth 45 and the lower portion of the thrust member 30 are invariabl embedded in a dense structure, formed usua ly of cuttings which have been saturated with the mud suplied through the passage 51. A material ack-pressure is thus built upon this passage, and the difference in pressure between this passage and that portion of the well into which the orifice 63 discharges, is ordinarily very great.

The position of the nozzle body 62 relative to the shank 21 is ordinarily adjusted at the factory, the determining factor in this adjustment bein the determination of the most efficient position of the jet formed bythe orifice 63 relative to the cutter 33. As previously mentioned, the osition of this jet may 4be readily changed y rotating the -nozzle body 62 relative to the shank 21. The nozzle body 62 ordinarily fits rather tightly in the side passage 61 so as to prevent any turning thereof during the operation of the bit.

It should be understood that our invention is not limited to the particular type of bit shown in the drawings, but is useful on various other types of rotary bits wherein it is desirable to directa jet of fluid tangentially against a cutter for the purpose of preventing the accumulation of foreign matter between the teeth thereof.

Uur invention in its broad concept consists of a bit having a cutter which rotates on the body, and the body has means for directing washing fluid against the cutter (preferably tangentially) and between the teeth as they rotate beneath the means which forms the washing stream.

We claim as our invention:

1. In a rotary bit, the combination of: a shank; a cutter rotatable on said shank and adapted to rotate as said shank rotates; and

nozzle means for directing a flow of fluid tangentially against said cutter, said nozzle means comprisin a nozzle body rotatably mounted in said s ank and providing an eccentric orifice.

2. In a rotary bit, the combination of: a shank; a cutter rotatable on said shank and adapted to rotate as said shank rotates; nozzle means for directing a flow of fluid tangentially against said cutter; and means for adjustably connecting said nozzle means to said halk to change the path of said flow of 3. In a rotary bit, the combination of: a shank providing a fluid passage; a pin on said shank, the axis of said pin being oblique to the axis of rotatidn of said shank; a cutter rotatable on said pin; teeth extending outward from said cutter; nozzle means comd municating with said fluid passage; and means for supplying fluid under pressure to said fluid passage while saidlbit is being used said nozzle means directing a flow of said fluid tangentiall against said cutter in a manner to clean the spaces between said teeth, and said nozzle means including a nozzle body rotatably mounted in said shank and providing an eccentric orifice.

4. In a rotary bit, the combination of: a shank providing a fluid passa e; a pin on said shank, the axis of said pin eing oblique, to the axis of rotation of said shank; a cutter rotatableon said pin; teeth extending outward from said cutter; nozzle means communicating with said fluid passage; and means supplying fluid under pressure to said fluid passage while said bit is being used, said nozzle means direbting a flow of said fluid tangentially against said cutter in a manner to clean the spaces between said teeth, and said nozzle means includes a nozzle body rotatably mounted in said shank and providing an .eccentric orifice formed therein and extending parallel to the axis of rotation of said nozzle body.

5. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on l tings,

said shank, said cutter having digging teeth on the lower part thereofand reaming teeth on the upper part thereof, there being means in said shank for delivering rotar fluid to said digging teeth for mixmg wit 1 the cuttings, and for directing a separate stream of rotary 'fluid against said reaming teeth.

6. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on said shank, said cutter having digging teeth on the lowerpart thereof and reaming teeth on the upper part thereof, there being means in said shank for delivering rotary fluid to said di ging teeth for mixing with the cuttings, ancI for directing a separate stream of rotary fluid against said reaming teeth and said digging teeth.

7. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on said shank, said cutter hav n digging teeth on the lower part thereof and reaming teeth on the upper part thereof, there being means in said shank for delivering rotary fluid to said digging teeth for mixing with the cutand for directing a separate stream of rotary fluid along one side of said cutter to wash the cuttings from said lreaming and digging teeth.

8. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on said shank, said cutter having digging teeth on the lower part thereof forming a pocket and reaming teeth on the upper part thereof, there being means in said shank for delivering rotary fluid to said pocket formed by said igging teeth for mixing with the cuttings, and for directing a separate stream of rotary fluid against said reaming teeth.

. 9. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on said i los shank, said cutter having digging teeth on the lower' part thereof forming a pocket and reaming teeth on the upper part thereof, there being means in said shank for delivering rotary fluid to said pocket formed by said digging teeth for mixing with the cuttings, and for directing a separate stream of rotary fluid along one side of said cutter to wash the cuttings from said reaming and digging teeth.

10. In a rotary bit, the combination of: a shank; and a cutter rotatably mounted on said shank, said cutter having digging teeth on the lower part thereof and reaming teeth on the upper part thereof, there being means in said shank for delivering rotary fluid to said digging teeth for mixing with the cuttings, and for directing a separate stream of rotary fluid to one side of said cutter to assist in carrying the cuttings upward in the well. 11. In a rotary bitthe combination of: a shank; and a cutter rotatably mounted on there being and reaming teeth o'n the upper part thereof,

means in said shank for deliverin rotary fluid to said pocket formed by sald digging teeth for mixing with the cuttings, and for directing a separate stream of rotary uid to one side of said cutter to assist in carrying the cuttings upward in the well.

.- In testimony whereof, the said JOHN A.

ZUBUN has hereunto set his hand at Los An eles, California, this 26th day of Decem er, 1928, and the said ELMER T. Soorrr has hereunto set his hand at Los Angeles, California, this 26th day of December, 1928.

JOHN A. ZUBLIN. ELMER T. SCOTT. 

